Flow battery

Abstract

A flow battery comprising a first tank for an anode electrolyte, a second tank for a cathode electrolyte, respective hydraulic circuits provided with corresponding pumps for supplying electrolytes to specific planar cells, provided with channels on the two mutually opposite faces for the independent conveyance of the electrolytes, mutually separated by electrolytic membranes and electrodes, the planar cells constituting a laminar pack, on at least one front of the laminar pack there being an end plate provided, on a first face, with at least one channel for the access of the electrolytes that arrive from the laminar pack, with at least one discharge channel for the conveyance of the electrolytes that originate from the access channel to at least one outlet that is connected to a respective tank, and at least one mixing channel.

The invention claimed is: 
     
       1. A flow battery of a type comprising a first tank for an anode electrolyte, a second tank for a cathode electrolyte, respective hydraulic circuits provided with corresponding pumps for supplying electrolytes to specific planar cells, provided with channels on two mutually opposite faces for the independent conveyance of said electrolytes, mutually separated by electrolytic membranes and electrodes, wherein said planar cells are mutually aligned and arranged side-by-side so as to constitute a laminar pack, on at least one front of said laminar pack there being an end plate provided, on a first face, with at least one channel for the access of the electrolytes that arrive from said laminar pack, with at least one discharge channel for the conveyance of the electrolytes that originate from said access channel to at least one outlet that is connected to a respective tank, and at least one mixing channel that is connected to said at least one outlet, said end plate being provided, on a second face, with a cavity to a bottom of which the at least one said access channel, the at least one said discharge channel and the at least one said mixing channel lead, said cavity accommodating a respective valve provided with at least one duct for the selective connection of said at least one access channel either to the at least one said discharge channel or to the at least one said mixing channel. 
     
     
       2. The flow battery according to  claim 1 , wherein said cavity has a substantially disk-like shape and is provided, on the bottom, with at least one hole that corresponds to at least one opening selected between a terminal end of said at least one access channel, an initial end of said at least one discharge channel and an initial end of said at least one mixing channel. 
     
     
       3. The flow battery according to  claim 2 , wherein said valve has a shape and dimensions that are complementary to those of said cavity for sealed rotary accommodation within said cavity, said valve comprising at least one substantially U-shaped duct that has at least one intake passage and at least one exit passage, which face and are proximate to at least one respective opening selected between the terminal end of said at least one access channel, the initial end of said at least one discharge channel and the initial end of said at least one mixing channel, which are present on the bottom of said cavity. 
     
     
       4. The flow battery according to  claim 3 , wherein said valve can move from a first configuration, in which its intake passages are connected hydraulically to a respective terminal end of said at least one access channel and its exit passages are connected hydraulically to a respective initial end of said at least one discharge channel, to a second configuration, in which its intake passages are connected hydraulically to a respective terminal end of said at least one access channel and its exit passages are connected hydraulically to a respective passage port of said mixing channel. 
     
     
       5. The flow battery according to  claim 1 , wherein said access channels are two in number and said discharge channels are two in number, said channels being arranged symmetrically with respect to the centerline of said end plate. 
     
     
       6. The flow battery according to  claim 1 , wherein said mixing channel has an initial end constituted by two passage ports and a terminal bifurcation having branches which lead into the two outlets of said end plate into which said discharge channel also leads. 
     
     
       7. The flow battery according to  claim 6 , wherein said branches of said mixing channel comprise respective shunts that are open outwardly for coupling to a corresponding sensor, which is external to said laminar pack, for detecting a value selected among electrolyte pressure, differential pressure of the electrolytes in the two branches, flow-rate of the electrolyte, relative flow-rates of the electrolytes in the two branches, temperature of the electrolyte, and differential temperature of the electrolytes in the two branches. 
     
     
       8. The flow battery according to  claim 1 , wherein said end plate comprises two through channels for introducing the electrolytes in the laminar pack. 
     
     
       9. The flow battery according to  claim 8 , wherein said through channels comprise respective shunts which are open toward the outside for coupling to a corresponding sensor, which is external to said laminar pack, for detecting a value selected among electrolyte pressure, differential pressure of the electrolytes in the two channels, flow-rate of the electrolyte, relative flow-rate of the electrolytes in the two branches, temperature of the electrolyte, and differential temperature of the electrolytes in the two branches. 
     
     
       10. The flow battery according to  claim 1 , wherein said laminar pack and said end plate are arranged on the top of an enclosure that contains said first and second tanks, producing a vertical extension of the battery with consequent minimum transverse space occupation.